Modelling the tide

A team of engineering researchers in Wales aim to accurately predict the impact of using the world’s second highest tidal range as a source of energy.

A team of engineers from Cardiff University aim to accurately predict the impact of using the world’s second highest tidal range as a source of energy.

To do so, the researchers at the university’s hydro-environmental research centre have designed and built Wales’ first physical model of the Severn estuary. Funded by the Welsh Assembly Government’s Welsh European Funding Office (WEFO), it will be used to more accurately study the impact of proposed Severn tidal power projects, including a barrage and other forms of tidal renewable energy.

The 6m x 4m model is designed to resemble as closely as possible all the unique characteristics of the estuary which stretches from west of Carmarthen Bay (near Tenby) to Gloucester.

Built in collaboration with engineers from Swansea University, the model features a computer controlled oscillating weir, which is used to generate tides of varying amplitude and period. It has a removable model barrage that allows conditions before and after the construction of the barrage to be simulated. It also allows for the impact of other tidal energy devices, including tidal lagoon and tidal stream turbines, to be examined.

‘The Welsh Assembly and UK government are currently undertaking a feasibility study on the effect that different options for a barrage and lagoons would have – for example on flooding risk and siltation,’ said Jane Davidson, the Welsh Assembly Government’s minister for environment, sustainability and housing.

‘A number of studies relating to the potential impact of a barrage have been carried out since the proposal was first mooted. However, this physical model, which is close in design to the actual basin, will enable us to look in-depth and over the long term at the potential impact of a barrage or other tidal-range development on the surrounding aquatic environments and habitats,’ added Prof Roger Falconer, who is leading the research team.

One option for a Cardiff to Western Barrage would stretch from Lavernock Point to Brean Down at an estimated cost of around £15bn. The massive structure could potentially harness the tidal energy of the Severn estuary and, within 14 years, could generate about five per cent of the UK’s supply of electricity.